Isobutyl ester of para-amino-benzoic acid.



. No Drawing.

UNITED STAT n w Winn.

WILHELM GRI J 'TTEFIEN, OF VOHWINKEL, NEAR ELBERFELD, GERMANY, ASSIGNOR T0 FARBENEABRIKEN VORIVL FRIEDR. BAYER & 00., OF ELBERFELD, GERMANY,

A CORPORATION OF GERMANY.

ISOBUTYL ESTER OF PARA-AMINO-BENZOIC ACID.

aminobenzoic acid or its derivatives with isobutyl alcohol or its derivatives.

' The new ester is a valuable compound having anesthetic properties, forming salts with acids which also produce local anesthesia and is probably produced according to the following formula:

In order to illustrate the new process more fully the following example is given, the parts being by weight: A mixture of parts of para-aminobenzoic acid, 50 parts of isobutyl alcohol and 10 parts of concentrated hydrochloric acid (1.19 sp. g.) is saturated with h drochloric acid gas while the mixture is belng heated to about 100 C. for several hours. After cooling, the prod- Specification of Letters Patent.

Application filed August 17, 1909. Serial No. 513,335.

Patented May 17, 1910 not of reaction is dissolved in water, the

aqueous solution is rendered alkaline and is then shaken with ether. The new ester is then obtained as the hydrochloric acid salt-by passing hydrochloric acid gas into the ethereal solution. The hydrochlorid melts at about 242 C. From the hydrochlorid, the free ester can be obtained by treatment with a solution of carbonate of sodium. It is a white powder soluble in alcohol, benzene and ether but only with difficulty in water. It crystallizes from ligroin in the shape of white needles melting at 65 C.

I claim g The herein described isobutyl ester of para-aminoben zoic acid, obtainable from this acid and isobutyl alcohol, which ester crystallizes from ligroin in the shape of white needles melting at 65 C., soluble in alcohol, benzene and ether and scarcely soluble in water, forming salts with acids which retain the valuable therapeutic properties exhibited by the ester, substantially as described.

In testimony whereof I have hereunto set my hand'in the presence of two subscribing witnesses.

WILHELM eafirrurmr. [a 8.]

Witnesses:

O'r'ro Komo, WILLY KLEIN. 

